John brisacher



1. BRISACHER. MEANS FOR TIGHTENING EYEGLASS LENSES.

APPLICATION FILED FEB. 10. I9I9.

1,304,850. Patented May 27, 1919,.

.lnventoz: QM

JOHN BRISAGHER, OF TORONTO, ONTARIO, CANADA.

MEANS FOR TIGHTENING EYEGLASS-LENSES.

Specification of Letters Patent.

Patented May2'7, 1919.

Application filed February 10, 1919. Serial No. 276,042.

To all whom it may concern:

Be it known that I, JOHN BRISACHER, a citizen of the Republic ofSwitzerland, and resident of the city of Toronto, county 01": York,Province of Ontario, in the Dominion of Canada, have invented certainnew and useful Improvements in Means for Tightening Eyeglass-Lenses, asdescribed in the following specification and illustrated in theaccompanying drawings, that form part of the same.

The principal objects of this invention are, to eliminate thedisagreeable conditions of loose eye glass lenses, and to provide ameans whereby the lenses may be effectively tightened after havingbecome worn.

The principal feature of the invention consists in providing variousthicknesses of packing strips for insertion between the arched portionof the bridge strap and the lens to take up the wear in the lens or lensholding pin;

In the drawings, Figure l is an enlarged elevational view of a portionof an eye glass bridge, lens strap and lens showing the application ofmy improved form of adjustment.

Figs. 2, 3 and 4 are enlarged perspective views of the graduated formsof adjusting strips to be used in carrying this invention into eifect.

It is a well known fact that the lenses of rimless eye-glasses workloose in the fitting through the strains to which they are subjected andit is erroneously considered that the arched portion of the lens strapbecomes bent or spread in such a manner as to allow the lens to loosen,but what actually takes place is that the constant straining between thelens and the holding strap works the pin, which extends through the holein the lens, so as to pulverize the glass at the edges of the hole andgradually enlarge the hole, thus loosening the lens.

It has been the practice with Opticians when lenses become loose to bendthe points of the arched portion to meet the edge surface of the lensand thus tighten the glass and it has been proposed in the prior art toinsert spring members which would automatically take up such wear. Screwadjustments have also been proposed but none of these, however are foundto be reliable, as it is found in practice that an arched connection isnecessary to the proper maintenance of a secure holding.

In carrying my invention into effect, I provide a series of thin metalstrips which are shown in the accompanying drawings very muchexaggerated. These strips areof several thicknesses and are suitablynumbered, such as 1, 2 and 3, etc., which numbers indicate the relativethickness.

Each of the strips is provided with two pairs of lugs a which areadapted to engage the sides of the portion 6 of the bridge B, one pairof said lugs fitting each side of the strap 0 which embraces the lens D.

The strips A are placed between the lens and the member I) and take upthe actual wear in the hole through the lens or on the pin 0 whichextends through the lens. When further wear occurs a thicker member Acan be used. I

This arrangement of a series of packing strips of different thiclmessesallows the optician to fit the lens in a repair job assecurely andsolidly as in fitting a new lens.

What I claim as my invention is 1. Means for tightening eye glasslenses, comprising, a thin packing strip adapted to be inserted betweenthe lens and the bridge strap to take up the wear, said strip having twopair of laterally turned lugs arranged at each side of the bridge strapto hold the strip in place.

2. Means for tightening eye glass lenses, comprising, a series of thinmetal strips of graduated thicknesses adapted to be placed between thelens and the bridge and having side holding lugs to secure them inposition.

JOHN BRISACHER.

- Copies of this patent may be obtained for five cents each, byaddressing the Commissioner out Patents,

Washington, D. C.

